In the past, an optical measurement method has been known for a measurement apparatus. The method employs a slab-type optical waveguide. The method excites labeled fluorescent bodies which exist in the vicinity of the surface of the optical waveguide using evanescent wave components from the optical waveguide. To actualize the optical measurement method, an apparatus is proposed as is illustrated in FIG. 15. In the apparatus, a test liquid housing chamber 92 is formed in one body at one face of a slab-type optical waveguide 91. An exciting light radiated from a laser light source or the like, which is not illustrated, enters into the optical waveguide 91 through a dichroic mirror 93. Fluorescent light radiated from labeled fluorescent bodies exits through the optical waveguide 91, and is radiated by the dichroic mirror 93 so as to be introduced into a detector 95 through an optical filter 94.
When the above-mentioned arrangement is employed, antibodies 96 are previously fixed on a surface of the optical waveguide 91. Antigens 97 in a test liquid are then bound by the antibodies 96, and then fluorescent labeled antibodies 98 (which are made by labeling antibodies with fluorescent bodies) are bound by the antigens 97. That is, the quantity of bound fluorescent labeled antibodies 98 is determined based upon the quantity of antigens 97 in the test liquid. And, an evanescent wave component is obtained by introducting an exciting light into the optical waveguide 91. Only the label fluorescent bodies 98a of the bound fluorescent labeled antibodies 98 are excited by the evanescent wave component so that the label fluorescent bodies 98a radiate fluorescence. Therefore, the intensity of radiated fluorescence is in proportion to the quantity of the antigens 97 in the test liquid. Further, the fluorescence is guided in the optical waveguide 91. Consequently, existence or non-existence or a degree of immnoreaction is measured by reflecting only the guided fluorescence by the dichroic mirror 93, cutting off the exciting light component with the optical filter 94, and introducing the fluorescence into the detector 95.
To perform an immunological measurement using the fluorescence immunological measurement apparatus having the above-mentioned arrangement, pre-processing for diluting the test liquid including antigens 97 with a dilution liquid is necessary prior to housing the test liquid and the fluorescent labeled antibodies 98 in the test liquid housing chamber 92.
FIG. 16 is a diagram explaining a conventional method employed in a fluorescence immunological measurement apparatus having six measurement units when the above-mentioned immunity measurement is carried out. In FIG. 16, T1 represents a preparation time until the beginning of a primary reaction, that is, a preparation time until the diluted test liquid is poured in the test liquid housing chamber 92 acting as a reaction vessel. T2 represents the primary reaction time of the immunological reaction, that is, a reaction time for the reception of the antigens 97 in the test liquid by the antibodies 96 which were previously fixed on the surface of the test liquid housing chamber 92. T3 represents a time period from B/F separation to the beginning of a secondary reaction, that is, a time period for discharging the test liquid in the test liquid housing chamber 92 and for pouring reagent which includes fluorescent labeled antibodies 98 in the test liquid housing chamber 92. T4 represents a light measurement time, that is, a time for measuring the fluorescence radiated by the label fluorescent bodies 98a of the fluorescent labeled antibodies 98 which have been received by the antigens 97. In the fluorescent immunological measurement apparatus, when measurement of the six measurement units is carried out using one pouring apparatus and one measurement data detection system, the preparation time T1 and the primary reaction time T2 must satisfy the equation of T1.times.5.ltoreq.T2, because two measurement units cannot be processed simultaneously.
But, the preparation time T1 greatly varies depending upon the content of the pre-processing assigned to the measurement units, that is, the content of the diluting processing of a test liquid.
Hereinafter, great variation of the preparation time T1 is specifically described by taking different cases as examples. One case is a case where a dilution magnification of a test liquid is determined to be about 50 times, which is a standard dilution magnification (hereinafter referred to as case A). Another case is a case where dilution magnification of A test liquid is determined to be about 50.times.50=2500 times, for example (hereinafter referred to as case B). A further case is a case where the quantity of the test liquid is great and the waste quantity caused by stirring the liquid in another vessel and sucking the liquid from the other vessel is required to be less (hereinafter referred to as case C).
In the case A, a dilution liquid is sucked from a dilution liquid vessel and a test liquid is sucked from a test liquid vessel. The sucked dilution liquid and test liquid the are poured into a stirring vessel, and both liquids are stirred in the stirring vessel so that the test liquid is diluted. Thereafter, the diluted test liquid in the stirring vessel is sucked and poured into a test liquid housing chamber 92 which is used as a reaction vessel so that preparation for measurement is performed. A required time for these processings is 80 seconds.
In the case B, a buffer liquid stored in a bottle or the like is sucked and a test liquid in a test liquid vessel is sucked, and the buffer liquid and the test liquid are discharged and stirred in a stirring vessel so as to generate a first diluted test liquid (for example, a 50-times diluted test liquid). Such processings are a first stage. Then, the buffer liquid stored in the bottle or the like is sucked, the first diluted liquid and the buffer liquid are discharged into a multi-function vessel and are stirred so as to generate a second diluted liquid (for example, 50-times.times.50-times=2500-times). In these processings, a required time for generating the first diluted liquid is 50 seconds, and a required time for generating the second diluted liquid from the first diluted liquid is 80 seconds. Therefore, 130 seconds is required for all of the processings.
In the case C, a dilution liquid is sucked from a dilution liquid vessel and a test liquid is sucked from a test liquid vessel, and the sucked dilution liquid and test liquid are discharged into a test liquid housing chamber 92 which is used as a reaction vessel. Both liquids are stirred for diluting the test liquid so that preparation for measurement is performed. A required time for these processings is 60 seconds.
When the case A, case B and case C exist in a mixed condition, the required time of 130 seconds of the case B which takes the longest time for diluting processing should be determined to be the standard required time for carrying out measurements using six measurement units. From the relationship of T1.times.5.ltoreq.T2, the relationship of 130 seconds.times.5.ltoreq.650 seconds is obtained whereby the primary reaction time T2 should be determined to be mope than 650 seconds.
However, 650 seconds is much longer than 420 second {80 seconds.times.5+20 seconds (margin)=420 second, including a little margin to avoid to overlap of T1 and T3} for six measurement units. A disadvantage arises in that a measurement time of a measurement apparatus becomes longer. It will be described in detail with reference to FIGS. 16-19 that a measurement time becomes longer.
[When six of case A types are measured]
FIG. 16 is a timechart for when a time interval between measurement units is determined to be 80 seconds and six case A types are measured.
In the first measurement unit, T1=80 seconds, T2=650 seconds (fixed), T3=80 seconds, T4=70 seconds, and a total time becomes 880 seconds. And, to finish measurement from the first measurement unit to sixth measurement unit, measurements are carried out 5 times and every 80 seconds sequentially after the first measurement unit for every measurement. Therefore, a measurement time till a measurement by the sixth measurement unit will be finished is necessarily 880 seconds+80 seconds.times.5=1280 seconds.
[When three case B types are measured]
FIG. 17 is a timechart for when three case B types are measured. In the first measurement unit, T1=130 seconds, T2=650 seconds (fixed), T3=80 seconds, T4=70 seconds, and a total time becomes 930 seconds. Further, a preparation time T1 of case B is 130 seconds and is longer than a required time T3 of 80 seconds, therefore a processing of T3 for a prior measurement unit is carried out during a preparation time T1 for next measurement unit. And, measurements are carried out 2 times at 130 second intervals sequentially after the first measurement unit for every measurement. Therefore, a measurement time until a measurement by the third measurement unit will be finished is necessarily 930 seconds+130 seconds.times.2=1190 seconds.
[When six case B types are measured]
FIG. 18 is a timechart for when six case B types are measured. In the first measurement unit, T1=130 seconds, T2=650 seconds (fixed), T3=80 seconds, T4=70 seconds, and a total time becomes 930 seconds. And, to finish the measurements from the first measurement unit to the sixth measurement unit, measurements are carried out 5 times and every 130 seconds sequentially after the first measurement for every measurement. Therefore, a measurement time till a measurement by the sixth measurement unit will be finished is necessarily 930 seconds+130 seconds.times.5=1580 seconds.
[When three case B types and three case C types are measured]
FIG. 19 is a timechart for when three case B types and three case C types are measured. In this case, it is assumed that three case C types are measured, and then three case B types are measured. In the first measurement unit, T1=60 seconds (a preparation time for case C), T2=650 seconds (fixed), T3=80 seconds, T4=70 seconds, and a total time becomes 860 seconds. And, time T3 of 80 seconds is longer than the preparation time T1 for case C from the first to third measurement units, thereby measurements are carried out by determining a time interval between measurement units to be 80 seconds. From the fourth to the sixth measurement units, processing of T3 is carried out within 130 seconds, which is the preparation time T1 for case C. Therefore, a measurement time for finishing measurements by the first to the sixth measurement units is necessarily 860 seconds+80 seconds.times.3+130 seconds.times.2=1380 seconds.
When a primary reaction time T2 is determined to suit a measurement content which requires maximum preparation time as was described earlier, the measurement time becomes extremely longer for measurements of various combinations. A disadvantage arises in that the efficiency of measurement is lowered.
In the foregoing, the description was made by taking a fluorescent immunity measurement apparatus as a measurement apparatus. Disadvantages which are similar to that of the above-mentioned fluorescent immunity measurement apparatus arise when a pre-processing and an after-processing are necessary and the pre-processing and the after-processing are carried out using a single processing apparatus in a measurement apparatus which performs measurement based upon absorption, diffusion, or polarization, or in a measurement apparatus utilizing bonding reaction other than an antigen-antibody reaction or a catalytic reaction such as an enzyme-reaction, because the processing apparatus cannot be used for plural measurement units simultaneously when measurements are carried out using plural measurement units sequentially.